MANGANESE SUPEROXIDE-DISMUTASE (MNSOD) AND AUTOANTIBODIES AGAINST MNSOD IN ACUTE VIRAL-INFECTIONS

Sera of 146 patients with acute EBV, HAV, HBV, CMV, HSV, and rubella v irus infections, and sera from 35 healthy controls were tested for the antioxidant enzyme manganese superoxide dismutase (MnSOD). An enzyme immunoassay that detects all isomeres of the enzyme was developed. The mean MnSOD value of healthy controls was 107 ng/ml. In HAV, HBV and E BV infections characterized by viral replication in internal organs, t here was an average 5-fold rise of serum MnSOD, whereas in viral infec tions with low direct cytopathogenity, such as rubella, CMV and HSV, t he MnSOD levels showed only minor rises. These sera were also tested f or autoantibodies against MnSOD using a novel sensitive indirect enzym e immunoassay. The average IgM anti-MnSOD concentration in sera of hea lthy controls was 112 GU. In sera of patients with acute HBV, CMV, HSV or rubella virus infections IgM anti-MnSOD values were only slightly raised above the cut-off level. In contrast, in some patients with acu te EBV infections anti-MnSOD concentrations rose up to 20-fold of norm al values. In HAV infections the same phenomenon was observed in patie nts who had reactivated EBV infections. These findings indicate that E BV may facilitate the B-cell response to MnSOD. These autoantibodies m ay inhibit the protective function of MnSOD and prolong the disease by oxygen injury. Our concept on the pathogenic effect of the autoantibo dies against MnSOD emphasizes the importance of the antioxidant enzyme in viral infections. (C) 1998 Wiley-Liss, Inc.